The current migration discourse with its concept complexes "hybridity", "diversity" and "transculturality", which are inspired by postmodernism, appears increasingly paradoxical and presents contradictions which complicate communication in science, politics and planning. Here, critical positions aiming at hegemonial ascriptions are contrasted with cosmopolitical positions with their liberal formulation of goals as well as with transgressive positions, often within the frame of a single concept. These apparent contradictions can be resolved by a systematic examination of the (post-)modern observer positions and planning horizons in the discourse. From an analysis of the current concepts, four fundamental impulses or "moments" are derived which are driving the migration discourse. With the help of these moments, different discourse positions can be more easily classified and compared, and, on the other hand, the challenges of an increasingly postmodern society for politics and planning can be formulated in a more stringent way.